Portable vertical underground storage tank



April 21, 0 R. H. ROHMER PORTABLE" VERTICAL UNDERGROUND STORAGE TANK I Filed Feb. '2, '1968 m; f 5 w a fl IIIIIIIIIIII. E 2 m m k n u u n w L 2 b r J1. w v

INVENT R RICHARD H. ROHME B QJULWJ JV 2LQ-/\ i;1 ATTORNEY United States Patent O 3,507,120 PORTABLE VERTICAL UNDERGROUND STORAGE TANK Richard H. Rohmer, 74 Sandringham Drive, Toronto 12, Ontario, Canada Filed Feb. 7, 1968, Ser. No. 703,629 Int. Cl. B65g 3/02, 5/00 US. Cl. 61-5 2 Claims ABSTRACT OF THE DISCLOSURE A portable vertical underground storage tank for the storage of liquid and bulk materials such as at gasoline service stations, the tank being installed in a vertically dug hole and readily removable for reinstallation at a new site.

BACKGROUND OF INVENTION At the present time, it is the practice, particularly for gasoline service stations, to install underground storage tanks in a horizontal position and the installation is of a permanent nature. Such horizontal installation results in a large disturbance of ground area and the tanks are not readily removable. For these reasons underground storage tanks of the ordinary type are not satisfactory for use especially as regards the storage of gasoline at automobile service stations, and, in particular, for such stations which are of a temporary or portable nature. These and other disadvantages are overcome by a vertically installed underground storage tank constructed in accordance with the present invention and the method of installing them, in a vertically dug hole, as hereinafter described.

DESCRIPTION OF INVENTION In the following description, the invention will be described in use with a portable gasoline service station but it is to be understood that this is done for the purpose of illustration and not for the purpose of limitation. It will be apparent that the invention will be equally useful for permanent installations.

The storage tank for introduction into a vertically dug hole for the underground storage of liquids according the the present invention comprises in combination:

(a) An outer cylindrical casing open at the top and closed at the bottom, said casing having a tapering configuration from the top to the bottom;

(b) Removable ballast in the bottom portion of the casing; and

(c) A liquid storage tank remova-bly housed in said casing said storage tank 'being smaller in diameter than the casing and supported on said ballast.

In the preferred embodiment the removable ballast comprises a plurality of solid and heavy plate-like members of a diameter less than the diameter of the casing, each plate-like member having a centrally located lifting member attached to the upper surface thereof which can be connected to the lifting hook of a hoist, such as a mobile crane.

The method of installing the storage tank at the site of the service station comprises the steps of:

(a) Digging by mechanical or hand means a hole in the surface of the earth;

(b) Installing therein a casing having an open top end and a closed bottom end, the casing being of substantially the same length as the depth of the hole and formed with a light taper from the top end to the bottom end;

(c) Placing in the bottom portion of the casing sufficient removable ballast to hold the casing in said hole 3,507,120 Patented Apr. 21, 1970 against the lifting force of underground water which would tend to elevate said casing;

(d) Placing in said casing a storage tank of a diameter and height less than the diameter of the casing;

(e) Providing a means for preventing solid or liquid material gaining access into the space formed between the casing and the tank; and

(f) Filling the recess formed between the top of the tank and ground level with removable material.

The underground storage tank and the method of installing the same will be described simultaneously with reference to the accompanying drawing which is a vertical cross-section of the storage tank and related elements.

The first step is to dig a vertical hole 10 by conventional means such as by hand or by an auger of a size which will drill a hole having a diameter which will accomodate the underground storage tank in a vertical position with its related parts. The depth of the hole is suificient to house the tank and its related parts as hereinafter described. The hole must be vertical. There is installed in the hole 10 a metal or concrete casing 11 which is formed with a slight taper so that the walls of the casing 11 converge inwardly towards the bottom. The taper should not be less than three inches for a casing having an overall length of 20' and not greater than the difference between diameter of the casing and the diameter of the tank at the widest point. By way of illustration only, it is mentioned that in the present construction the top end of the casing 11 is eight feet in diameter and at the bottom it is three inches narrower in diameter. The purpose of this taper is to make the removal of the casing from the hole easy and without distorting the same.

The top end of the casing 11 is provided with lifting eyes 13, in the present illustration, there are four such eyes which are diametrically opposite each other and equally spaced about the circumference of the casing.

To prevent the casing being lifted by external forces such a water beneath the casing ballast is provided in the form of, in the present illustration, four concrete discs 14a, 14b, 14c, 14d in placed in the bottom of the casing as shown. Each concrete disc is slightly narrower in diameter than the casing and is provided with a lifting handle 15 to which can be attached the hook of a hoist whereby the discs can be lowered into the casing when installed or removed from the casing when it is desired to move the storage tank and casing to another site. There is then placed in the casing a gasoline storage tank 16 which stands in a vertical position on the uppermost ballast 14a. The overall height of the tank 16 is substantially less than the overall height of the casing 11 so as to leave a compartment thereabove which compartment will receive fill as hereinafter described. The tank is provided with at least two lifting eyes 17, three being shown. The lifting eyes 17 are attached to the outside surface of the tank adjacent to the top with equal spacing between them.

A removable ring 18 is placed on the top of the tank and spans the space 19 formed between the outer and inner walls of the tank and casing respectively. The ring 18 prevents earth and moisture from getting into the area 19. The area or space 19 allows the tank 16 to expand and contract by reason of temperature variations.

The space above the top of the tank 16, after installation is filled to grade level with earth material 20 which can be topped off with paving material.

The tank 16 is provided with the usual fill pipe 22 and the extraction supply pipe 21.

The manner of installing is as follows.

The hole 10 is dug by mechanical or hand means, in this case an eight-foot auger. The casing 11 is then installed; the ballast is then inserted; the tank 16 is then installed in place so that it stands on top of the uppermost ballast 14a. The ring 18 is then placed in position on top of the tank so as to span the area 19. The ring is installed, preferably, to form a fluid tight seal to prevent fluid and other matter flowing into the space 19. The space above the tank 16 is filled with material 20' and topped off with a servicing material in grade with the surrounding pavement.

To remove the tank the material 20 is first removed; then the ring 18. The tank is then raised with a suitable hoist by the lifting ears or lugs 17. The ballast is then removed and when that is done the casing 11 can be withdrawn from the hole by means of a hoist which is attached to the lifting edges 13. The taper of the casing 11 makes it possible to easily withdraw the casing from the hole Without causing any distortion of the casing during lifting and without requiring removal of earth from around the casing.

What I claim is:

1. Portable apparatus for removable introduction into a vertical hole for the underground storage of liquids comprising in combination:

(a) an outer cylindrical casing open at the top and closed at the bottom, said casing having a tapering configuration from the top to the bottom;

(b) removable ballast in the bottom portion of the casing; said removable ballast comprises a plurality of solid and heavy plate-like members of a diameter less than the diameter of the casing, each plate-like member having a centrally located lifting member attached to the upper surface thereof;

(c) a liquid storage tank removably housed in said casing, said storage tank being smaller in diameter than the casing and supported on said ballast;

(d) a removable flange at the top of the tank, said flange extending inwardly to completely cover the space between the outer wall of the tank and the inner wall of the casing; and

(e) at least two lifting lugs secured to and equally spaced around the outer wall of the tank at the top thereof; at least two lifting lugs secured to and equally spaced around the wall of the casing adjacent to the top thereof.

2. A method for providing the underground storage of liquids and the easy portability of the storage means from one location to another comprising the steps of:

(a) digging a vertical hole in the surface of the earth;

(b) installing therein a casing having an open top end and a closed bottom end, the casing being of substantially the same length as the depth of the hole and formed with a slight taper from the top end to the bottom end;

(c) placing in the bottom portion of the casing suflicient removable ballast to hold the casing in said hole against the lifting force of underground water which would tend to elevate said casing;

(d) placing in said casing a storage tank of a diameter and height less than the diameter of the casing;

(e) providing a means for preventing solid or liquid material gaining access to the space formed between the casing and the tank; and

(f) filling the recess formed between the top of the tank and ground level with removable material.

References Cited UNITED STATES PATENTS 2,286,221 6/1942 Merolle 22010 2,501,762 3/1950 Davis 22018 PETER M. CAUN, Primary Examiner US. Cl. X.R. 220-10, 18 

